public class SimpleFactoryUse
{
  public void Use()
  {
    // 用户选择支付方式
    var payment = PaymentFactory.CreatePayment(PaymentFactory.PaymentType.Alipay);
    payment.ProcessPayment(99.99m);

    payment = PaymentFactory.CreatePayment(PaymentFactory.PaymentType.WeChatPay);
    payment.ProcessPayment(150.00m);
  }
}